Apparatus for acquiring image and method for acquiring image

A method for acquiring an image, applied to an apparatus for acquiring an image, wherein the apparatus for acquiring an image comprises an image sensor, a light compensator, and a light filter assembly, the light compensator comprises a first light compensation apparatus, the light filter assembly comprises a first light filter, the image sensor is on a light output side of the light filter assembly, and the method comprises:

• performing near-infrared light compensation by the first light compensation apparatus, wherein the near-infrared light compensation is performed in at least part of an exposure period of a first preset exposure but is not performed in an exposure period of a second preset exposure, and the first preset exposure and the second preset exposure are two of a plurality of exposures performed by the image sensor;
• enabling visible light and part of near-infrared light to pass through the first light filter;
• and
• performing the plurality of exposures by the image sensor to generate and output a first image signal and a second image signal, wherein the first image signal is generated according to the first preset exposure and the second image signal is generated according to the second preset exposure;
• wherein, in a case that a central wavelength for the near-infrared light compensation by the first light compensation apparatus is a specified characteristic wavelength or falls within a specified characteristic wavelength range, a central wavelength and/or a wave-band width of the near-infrared light passing through the first light filter meets) a constraint condition;
• and
• wherein the constraint condition comprises:
• a difference between the central wavelength of the near-infrared light passing through the first light filter and the central wavelength for the near-infrared light compensation by the first light compensation apparatus is within a wavelength fluctuation range, and the wavelength fluctuation range is 0 nm to 20 nm;
• a semi-bandwidth of the near-infrared light passing through the first light filter is less than or equal to 50 nm;
• a first wave-band width is less than a second wave-band width, wherein the first wave-band width is a wave-band width of the near-infrared light passing through the first light filter;
• and the second wave-band width is a wave-band width of near-infrared light blocked by the first light filter;
• or
• a third wave-band width is less than a reference wave-band width, wherein the third wave-band width is a wave-band width of near-infrared light with a passing rate being greater than a specified proportion, and the reference wave-band width is any wave-band width in a wave band range of 50 nm to 150 nm.